“My sister is in a badass place right now,” the country singer-songwriter, 25, says of her pop counterpart, 34.
“I think we need to focus on what an amazing place everyone is in, especially her,” Jamie Lynn adds. “She’s kicking ass right now!”
Indeed, Britney – who in May performed a showstopping medley of hits at the Billboard Music Awards, where she took home the Icon Award – is in the third year of her Piece of Me residency at The Axis at Planet Hollywood Resort and Casino in Las Vegas, a gig she’ll maintain for at least two more years.
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As Britney told PEOPLE in an exclusive 2015 cover interview, “I’m in a real good place,” adding at the time: “I’m very blessed.”
Like her sister, Jamie Lynn is crushing it in her career, too. She scored a No. 5 Hot Country Song with “I Got the Boy,” the 2015 track she co-wrote for Jana Kramer; she played new music at her Grand Ole Opry debut in March; she’ll release her new single, “Sleepover,” on June 24; and on June 26, her documentary, Jamie Lynn Spears: When the Lights Go Out, airs at 10/9c on TLC.
Both the Spears sisters have bravely pulled through public growing pains. In 2008, one-time Nickelodeon star Jamie Lynn faced backlash when she, at age 16, gave birth to daughter Maddie; the same year Britney was placed under a court-approved conservatorship following a breakdown.
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But Jamie Lynn says their struggles have only made them stronger.
“We are really honest,” says Jamie Lynn. “If my family is going through something, we don’t try to pretend we’re perfect because we’re not. To the public, that can look like we’re falling apart. But to us, it’s just going through life.”
The youngest Spears adds that those struggles have also shaped them into the resilient women they are.
“What you learn is: no one defines you. As long as you’re honest and hold yourself accountable, I don’t believe that the outside defines you,” she says. “I choose to embrace the good.”
These days, Jamie Lynn and Britney are as focused on their families as they are their careers. Four years after splitting from Maddie’s father, Jamie Lynn married businessman Jamie Watson, and the couple live in Louisiana with Maddie, now 8. Meanwhile, Britney spends plenty of quality time with her sons Sean Preston, 10, and Jayden James, 9, (with ex Kevin Federline) thanks to the flexible schedule her Vegas residency provides.
“We spoil each other’s kids. I get to have the boy time with them, and Britney gets to play dress-up with Maddie,” says Jamie Lynn. “I think it’s more of a joy having a sister who has kids, too.”